Title: Modeling and stock assessment of Prince William Sound herring
Project Year and Number: 2019: 19120111-C
Other Fiscal Years and Numbers for this Project: None
Principal Investigator (PI): Trevor Branch, University of Washington
Assisting Personnel: None
Restoration Category: Research
Abstract: Prince William Sound (PWS) herring collapsed shortly after the Exxon Valdez oil spill and has yet to recover. Here, we propose a modeling component to the long-term herring monitoring project, which has as its chief goal an understanding of the current status of PWS herring, the factors affecting its lack of recovery, and an assessment of research and fishery needs into the future. The original proposed project was expanded in FY18 with the addition of a postdoctoral fellow to investigate linkages between PWS herring recruitment to environmental forcing. Key products are the following (items 6-9 are related to the postdoctoral fellow): 1. The core product of the modeling project is the maintenance and updating of the new Bayesian age-structured assessment (BASA) model based on the ASA model used by ADF&G, including annual assessment updates of PWS herring and the revision of BASA to fit to new data sources such as the age-0 aerial survey, condition data, and updated age at maturity. 2. Adapting the BASA model to better model the disease component of natural mortality. Specifically, this would be based on new methods for detecting antibodies of viral hemorrhagic septicemia virus (VHSV) in archival and planned future collections of herring serum using a plaque neutralization assay (described by Hershberger). 3. Continued collection and expansion of catch, biomass, and recruitment time series from all herring populations around the world to place the lack of recovery of PWS herring into context given patterns of change in herring populations around the world. 4. An initial exploration of factors that may be used to predict herring recruitment, including oceanography, climate, competition, and predation. 5. A management strategy evaluation to test alternative harvest control rules for managing the fishery in the future, given realistic variability in productivity over time, and the possibility that the population has moved into a low productivity regime. Ecological, economic and social factors would be considered in the MSE. 6. Identifying relationships among oceanographic, biological, and climate data series from within PWS, the Gulf of Alaska, and the North-east Pacific that can predict PWS herring spawning, survival, and recruitment. 7. Examination of physical and ecological processes linked to PWS herring spawning, spawning survival, and survival of juvenile life stages. 8. The relative influence of physical and ecological processes on recruitment to the PWS and Sitka Sound herring populations. 9. Identifying environmental inputs for incorporation into the BASA model to improve recruitment predictions.
No keywords defined.
Proposal: View PDF (609 KB)
Funding Recommendations: View
Funding Detail For: 2019
Quarterly Project Tasks For: 2019
Annual Report: 2019: Due 03/01/2020
Final Report: Draft Final Report Due 4/15/20
Publications from this Project: None Available